1. Field of the Invention
The present invention relates to a sheet conveyance apparatus and an image forming apparatus including the sheet conveyance apparatus.
2. Description of the Related Art
In a conventional image forming apparatus such as an electrophotographic copying machine, a toner image formed on a photosensitive member or an intermediate transfer belt is transferred by a transfer roller onto a sheet conveyed by a registration roller. Then, the transferred toner image is fixed on the sheet by a fixing roller.
During the image forming process in which the sheet passes through the registration roller, the transfer roller, and the fixing roller, the sheet is nipped by the registration roller and the transfer roller, or nipped by all of the registration roller, the transfer roller, and the fixing roller.
In the actual image forming apparatus, there is a case where a misalignment or a pressure imbalance occurs among the registration roller, the transfer roller, and the fixing roller. In such a case, the sheet onto which a toner image is being transferred by the transfer roller may not be conveyed straight ahead. The sheet may become skewed or be conveyed in a skewed state. As a result, the position of the image transferred onto the sheet may deviate.
As a technique for preventing the positional deviation of the image with respect to the sheet, Japanese Patent Application Laid-Open No. 6-266181 discusses an adjustment device capable of adjusting the right and left heights of a conveyance guide.
However, with the configuration of the image forming apparatus discussed in Japanese Patent Application Laid-Open No. 6-266181, adjustment of the conveyance guide has to be performed by a user, and thus there has been a problem that the usability thereof is not good. Further, it may not be possible to prevent the positional deviation of the image with respect to each individual sheet.
There is an increasing demand for recent image forming apparatuses to further improve the usability and the image quality. Thus, it has been desired to improve the technique discussed in Japanese Patent Application Laid-Open No. 6-266181.